The invention is related generally to power-driven conveyors and, more particularly, to modular plastic conveyor belts constructed of a series of rows of long, flexible modules connected together by hinge rods.
Modular plastic conveyor belts are widely used to convey raw meat and poultry in processing plants. These belts are typically constructed of many stiff plastic belt modules arranged in a bricklay pattern. Each row of modules has leading and trailing hinge eyes that interleave with the hinge eyes of leading and trailing rows. The rows are connected serially together into an endless belt by hinge rods received in passageways formed through the aligned interleaved hinge eyes. The belt can articulate at hinge joints so formed between rows. These belts are looped between drive and idler sprockets or drums, which have driving structure, such as drive teeth, that engages drive members at drive locations spaced apart along the length of the belt. The spacing between consecutive drive locations in the direction of belt travel along the length of the belt defines the drive pitch of the belt. Typically, the drive pitch of a modular belt equals the length of each row to allow the modular belt made of stiff modules to wrap closely around the sprocket with good sprocket-belt engagement.
Belt sanitation is an important consideration in meat and poultry applications. Blood, fat, and other contaminants can hide in nooks and crannies in the structure of the belt. The hinged joints between belt rows and the seams between side-by-side modules in each row are two areas of a belt that can harbor these contaminants. Frequent washing by cleansers and water directed into these areas is necessary to attain the required degree of cleanliness that is so important in these food applications. But frequent washing is messy, time-consuming, and expensive. That's why there is an ongoing need for conveyor belts that are easier to clean.